NEED HELP FAST!!!!spitting,stumbling low throttle

[ibspoolin2]

ok heres the new problem. The problem this started happening before my fuel pump went. when i drive at low throttle (20% or lower) it like missess,spits,or stumbels. when it does this it runs real lean it hits like a 16-17:1 AFR. the other day my fuel pump shit on my so i replaced it with a walbro 255. i just swapped it today and took it for a test drive and it did fine. but when i took it out the second time it was spitting like a *****. so i changed the plugs and it got alittle better it only does it alittle now but only when its warm. it is really pissen me off i cant drive normal. the things i already checked plugs wires timing changed fuel filter. and there is no check engine light.WTF i give up
Thanks Kevin

 

[ibspoolin2]

Anyone?

 

[wickednightmare]

hey do you have fpr with that 255 if not u need one and adjust it to at least the stock fuel presure maybe that will help it out also check your 02 sensor

 

[ibspoolin2]

it did it before i had the walbro in. do i need to put a afpr in it? ill check the O2 should i just get a new one?

 

[wickednightmare]

it did it before i had the walbro in. do i need to put a afpr in it? ill check the O2 should i just get a new one?

yes i would def get a fpr to control that 255 i how old is the 02 if its old i would replace it... it wouldnt hurt any and a bad 02 can make u run rich fouling plugs making it sputter

 

[ibspoolin2]

its running lean when it spits not rich thanks for the help

 

[BigSorn]

check your mas.

 

[wickednightmare]

check your mas.

also a very good idea

 

[wickednightmare]

also a very good idea

## profile says you have an safc is that configed rite im not up to date with them i still run the tried and tru hks vpc to tune my car

 

[ibspoolin2]

yeah its hooked up right it started like 2 weeks after it was in though

 

[pSimytSi]

I may be having the same problem as you. Driving lightly with low throttle input it randomly goes real lean (for me it maxes my gauge at 18+) and spitters. The only way I can regain normal driving again is if I down shift or hold the clutch in until the rpms reach idle level. If I continue low throttle it seems to happen again and again every 5-30 seconds.

Fill me in if you reach an answer outside this thread.. I'll do the same.

 

[xxShaneOmac]

I have what seems to be the same exact problem.

94 NT Talon

When the car is cold it drivers perfect.

When the car is warm and i give a very very slight throttle, 5% and hold it at that % it starts to buck spit backfire jerk the car etc.

If I floor it the car runs smoth, but at very light throttle when warm it is hell to drive.

I have done

Oil Change
Oil Filter
Coolant Flush
Spark Plugs
Plug Wires
Fuel Filter
Air Filter

I thinking it has something to do with MAS, some major leaks on the intake, or the fuel dilevery system.

When my car is in open loop and it dosn't require any information to determine the A/F Ratio it drives fine, but at Closed loop when its warm and starts looking at numbers, It gets really jumbled down on the low throttle.

Lets keep this thread going tell we are fixed!

 

[pSimytSi]

I have what seems to be the same exact problem.

I have done

Oil Change
Oil Filter
Coolant Flush
Spark Plugs
Plug Wires
Fuel Filter
Air Filter

I thinking it has something to do with MAS, some major leaks on the intake, or the fuel dilevery system.


Lets keep this thread going tell we are fixed!

Amen!

I will be doing - air filter fuel filter and checking MAS plus plug gap tomorrow

I have some pretty decent air leaks though. The first big one I was able to fix and then my compressor broke(cheap tire emergency kit type) while I was looking for the next in line. Theres probably a good number more I'm sure. First BLT this car's ever had.

Are you running really lean while this happens Shane? I find just giving it more throttle when it does it to me, makes it sputter that much worse.

 

[xxShaneOmac]

Im not sure If I am running lean or not, This is on my DD NT no mod's besides a fart can from the previous owner.

I think it may have something to do with Im sucking in air and your blowing it from a turbo, but when I floor the gas my car runs great 24/7 no problem. Besides being NT the car pulls to to 6.5k at all times.

This is only affecting me when I have 5% or less throttle applied and the car is warm.

o2 Sensor
Fuel Pump
Injectors
MAS
ECU

Thoes are the only things I could think of that it could be.

Its an improper mixture at a certin area causing this problem as far as I could tell, maybe TPS.

ARG I hate this stuff sometimes.

 

[ibspoolin2]

ok guys this is what i did to fix most of my problem i switched the MAF. i almost completly fixed it. it does **** up at idle alittle when it sits for awhile but thats it now.

 

[Chengy]

ok guys this is what i did to fix most of my problem i switched the MAF. i almost completly fixed it. it does **** up at idle alittle when it sits for awhile but thats it now.

Thank you so much... I just switched mine out and it works fine now!

 

[xxShaneOmac]

Did you guys buy new ones?
Or the good ole junk yard?

 

[ibspoolin2]

no i got a used one. thats why it didnt fix it all the way i think

 

[Chengy]

Did you guys buy new ones?
Or the good ole junk yard?

Nope, I took it out of my other GSX and tried it and it worked. So I'm just buying a used one.

 

[ivatu]

thats the o2 all the way

 

[xxShaneOmac]

thats the o2 all the way

FYI this post dosn't give us much.
How do you know, do you have exact experance with this suiation?

Is it just an.. I think.

Give me a little more to go on before I have to buy a 80-120 dollar part.

 

[ivatu]

i want to know if only happens when idle and in low throttle and if it stops doing it when you accelerate hard WOT if it stops doing it at WOT its the o2 also try disconnecting the sensor and check if it still does it, if it doesnt do it after you desconnect the sensor then there you go. i had a problem with my car that it was spitting black smoke and also my a/f gauge was showing that i was running lean when actually i was running very rich so after i disconnected the o2 sensor problem solved the only thing is that you are going to get bad gas millage but thats why i put a new one.
ooo and sorry about that

 

[64_Frankenstein]

its running lean when it spits not rich thanks for the help

Check the o2 sensor and wiring harness.

 

[boogie]

ive been having a problem simular to you all i have a 93 plymouth laser n/t and i have this same hesitation at low idle mainly when the car comes to a complete stop then i have to drive again pulled the iacv motor and cleaned it that helped a little but not much i'm thinking about replacing the o2 sensor to see what happens

 

[ibspoolin2]

i found the last problem.. the sprak plugs had to be regapped. it fixed it